1. Field of the Invention
The present invention relates to a metal melting furnace such as that for aluminum and the like.
2. Description of the Related Art
The present inventor previously proposed a metal melting furnace 100 shown in FIGS. 10–12. This is a melting furnace 100 in which material to be melted is inserted into a preheating flue 122 having a material charging port 121 formed at the top thereof and an inclined hearth section 125 at the bottom thereof and, then, the material is heated and melted by a melting burner 135 disposed toward the lower portion of the preheating flue 122 and introduced into a molten material holding section 160 via the hearth section 125 and, in the molten material holding section 160, the molten material M is kept at a predetermined temperature by a holding burner 165, wherein a melted material holding member 115 having an open bottom is disposed in the preheating flue 122 so that there is a clearance C between the melting burner 135 and a furnace wall surface 111W at the opposite side in the flue 122. (for an example, see Japanese Patent No. 32250000)
In the figures, there are shown a furnace wall 111 defining the preheating flue 122, an inspection hole 112 formed on the furnace wall 111, a door 113 of the inspection hole 112, a flange section 116 provided at the top of the melted material holding member 115, a partition 126 between the preheating flue 122 and the molten material holding section 160, and a communicating opening 127 formed through the partition 126. Further, in connection with the molten material holding section 160, there are shown a furnace wall 161 defining the molten material holding section, an inspection hole 162 formed on the furnace wall 161, a door 163 of the inspection hole 162, a molten material discharge section 170, and a communicating opening 171 formed at the bottom of the partition between the molten material holding section 160 and the molten material discharge section 170.
In the conventional metal melting furnace 100 of this type, the melting burner 135 is typically disposed toward the bottom of the preheating flue 122 so that burner flame of the melting burner 135 hits the material to be heated and melted directly. The material naturally starts melting from the portion hit by the burner flame directly, but in a position where the burner flame of the melting burner 135 does not hit directly or adequately or, more specifically, for example, in a position adjacent to the hearth section 125 and a position at the opposite side of the melting burner 135, it may be hard to melt the material and, in some cases, the material may remain unmelted to the end.
Further, in the conventional metal melting furnace 100 in which the melting burner 135 is disposed on the furnace wall 111, when the burner flame hits the material to be melted directly, sherbet-like half-melted material may be scattered to deposit as oxides on the surface around the melting burner 135 and the inside thereof and, therefore, the oxides may have to be removed regularly.
In these respects, in the metal melting furnace of this type, it has been strongly desired to preheat and melt the entire material more efficiently and to facilitate operations for removing the oxides deposited on the surface around the melting burner and the inside thereof.
Japanese Patent No. 3225000